People with OCD may be diagnosed with other conditions, such as Tourette syndrome, compulsive skin picking, body dysmorphic disorder and trichotillomania. It is also interesting to note that there is some research demonstrating a link between drug addiction and obsessive compulsive disorder as well. There is a higher risk of drug addiction among those with any anxiety disorder (possibly as a way of coping with the heightened levels of anxiety), but drug addiction among obsessive compulsive patients may serve as a type of compulsive behavior and not just as a coping mechanism. Depression is also extremely prevalent among sufferers of OCD. One idea for the high depression rate among OCD populations was posited by Mineka, Watson and Clark (1998), who explained that people with OCD (or any other anxiety disorder, for that matter) may feel depressed because of an "out of control" type of feeling. There may also be a link between Autism and Asperger's and OCD.